1. Field of the Invention
The present invention relates to a storage system and its performance tuning method.
2. Description of Related Art
With the development of computer system technology, the use of storage systems is becoming diversified. Input/output (I/O) characteristics of a host computer that requests I/O processing to a storage system are also becoming diversified. In order to design a storage system having high performance in various types of I/O characteristics, it is desirable to perform optimal performance tuning to the respective I/O characteristics.
I/O characteristics of a host computer may change time to time. The temporal change of I/O characteristics can be broadly classified into a short-term change of I/O characteristics (for instance, change of I/O characteristics in a short cycle such as when backup processing is executed at night), and a long-term change of I/O characteristics (for instance, change of I/O characteristics in a long cycle such as when the load increases pursuant to the increase of I/O processing requests from the host computer).
Japanese Patent Laid-Open Publication No. H8-241227 discloses a method for evaluating the performance of an active storage system for the purpose of monitoring or predicting a state that will have an adverse effect on the performance of such storage system and, when it is detected that the performance is not optimal, warning the user to enable the user to take measures to improve the performance.